Capybara
The capybara holds the title of the largest living rodent on Earth, with adults commonly reaching 50 kg or more. A native of South America, it inhabits flooded grasslands, riverbanks, and wetlands from Venezuela to Argentina. Its body is built for water: the eyes, ears, and nostrils sit high on the skull so the animal can breathe and stay alert while almost entirely submerged. Partially webbed feet make it a capable swimmer, and it can hold its breath for up to five minutes to evade predators such as jaguars, caimans, and anacondas. Capybaras are highly social and live in groups that typically number between 10 and 20 individuals, though gatherings of over 100 have been recorded during dry seasons when resources concentrate around shrinking water bodies. They graze mostly on grasses and aquatic plants, and like other cavies they practice coprophagy, re-ingesting their own droppings to extract additional nutrients.
Habitat: Why do they need water?
Water is not simply a convenience for the capybara. It is a core requirement of daily life. Across South America, these animals settle along riverbanks, flooded grasslands, marshes, and the edges of lakes, always staying close to a reliable water source. Their skin dries out quickly under direct sun, so regular submersion helps them regulate body temperature and keep their skin in good condition. The skull is shaped so that the eyes, ears, and nostrils all sit near the top, allowing a capybara to breathe, hear, and scan for threats while nearly its entire body remains below the surface. When a jaguar, caiman, or anaconda approaches, the animal can slip underwater and hold its breath for up to five minutes, making rivers and wetlands both a home and a refuge.
Diet: Grass and special digestion
Grasses make up the bulk of the capybara's diet, supplemented by aquatic plants, fruit, and bark when the dry season reduces the availability of fresh pasture. Like all members of the cavy family, capybaras practice coprophagy, consuming their own droppings to recover nutrients that the digestive system did not fully absorb during the first pass. This behavior is not a sign of poor health. It is an efficient strategy shared with rabbits and several other herbivores. The front incisors grow continuously throughout the animal's life, keeping pace with the wear that comes from grazing on coarse vegetation. Capybaras also have a large fermentation chamber in the gut that helps break down the cellulose in plant material, a feature that makes their digestion surprisingly effective for an animal of their size.
Behavior: A very social animal
Few mammals are as consistently social as the capybara. Groups typically range from 10 to 20 individuals led by a dominant male, though during dry seasons, when shrinking water bodies concentrate both food and animals, gatherings of over 100 have been recorded. Living in a group offers real protection: more eyes and ears mean earlier warnings of approaching predators. Several bird species, including cattle tyrants and yellow-headed caracaras, routinely perch on capybaras and pick ticks and flies from their coats, a relationship that benefits both parties. Communication within the group relies on a range of vocalizations, including purrs, barks, and whistles, each carrying a different meaning. Females in a group will nurse one another's young, a behavior known as communal nursing that improves the survival of pups across the whole group.
Curiosities and History
During the 16th century, Catholic missionaries in Venezuela petitioned Rome to classify the capybara as a fish, citing its semi-aquatic lifestyle. The request was granted, which meant that its meat could be eaten during Lent and other days of fasting when red meat was forbidden. That classification has no scientific basis, but it shaped how many communities in South America related to the animal for centuries. Today, capybaras have become a genuine internet phenomenon, celebrated for their calm temperament and their apparent willingness to share space with other species. In several cities in Brazil, populations have adapted to urban green spaces and are regularly seen in parks alongside humans. In some rural areas they are farmed legally for meat and leather, while in others they are protected as part of local wetland conservation efforts.
Technical factsheet
Frequently Asked Questions
How big do capybaras get?
Capybaras are the largest rodents on Earth. Adults typically weigh between 35 and 66 kg and can measure around 1.2 meters in length. Males are generally smaller than females, which is unusual among mammals. Their stocky, barrel-shaped bodies and short legs give them a low center of gravity that serves them well both on land and in water. At full size, a capybara is roughly comparable to a large dog.
Where do capybaras live?
Capybaras are found across most of South America, from Venezuela and Colombia in the north down to Argentina and Uruguay in the south. They always settle near water: riverbanks, flooded grasslands, marshes, and lake edges are their preferred habitats. They cannot survive far from a permanent water source, as they rely on it for cooling, escaping predators, and finding much of their food. Some urban populations have also established themselves in parks in Brazilian cities.
What do capybaras eat?
Capybaras are herbivores that feed mainly on grasses. They also eat aquatic plants, fruit, and bark, especially during the dry season when fresh grass becomes scarce. Their continuously growing incisors handle coarse vegetation with ease, and a large fermentation chamber in their gut helps break down tough plant fibers. They also practice coprophagy, re-ingesting their own droppings to recover nutrients the digestive system did not fully absorb on the first pass.
What are the main predators of the capybara?
Capybaras face threats from several large predators across their range. Jaguars, caimans, and anacondas are their most significant natural enemies. Green anacondas, in particular, are well suited to ambushing capybaras near the water's edge. Pumas and ocelots also prey on them occasionally. Young capybaras are especially vulnerable and are targeted by birds of prey as well. Living in a group and staying close to water are the two main strategies capybaras use to stay safe.
Are capybaras dangerous to humans?
Capybaras are generally calm and non-aggressive toward people. In areas where they have grown accustomed to human presence, such as urban parks in Brazil, they often show little concern when people walk nearby. However, like any wild animal, they can bite if they feel cornered or threatened, and their teeth are strong enough to cause a serious injury. It is always best to observe them from a respectful distance rather than attempting to feed or touch them.
Are capybaras endangered?
The capybara is currently listed as Least Concern on the IUCN Red List, meaning the species as a whole is not at risk of extinction. Its wide distribution across South America and its ability to adapt to a range of wetland environments help maintain healthy populations. However, habitat loss due to agriculture and hunting for meat and leather do put pressure on local populations in some regions. In others, capybaras thrive and are even considered abundant.
Can capybaras be kept as pets?
Capybaras are kept as pets in some countries, though the practice is regulated or outright prohibited in many places. They are highly social animals that suffer when kept alone, so they require at least one companion of the same species. They also need constant access to a large body of water for swimming and skin health. Their care demands are significant: they eat large quantities of grass daily and need considerable outdoor space. Prospective owners should always check local laws first.